The Camshaft Position (CMP) sensor input is used to detect an engine misfire. The Powertrain Control Module (PCM) also uses the CMP sensor signal as an input for modifying the fuel injection timing and for modifying the ignition timing.

The PCM receives information on the engine status from various engine sensors and then selects the most appropriate ignition timing settings from within the PCM’s programming. The following are the most important inputs for determining ignition timing requirements: